A

PROJECT REPORT

ON

GEAR LESS TRANSMISSION

SUBMITTED BY

--------------------------

HOD PROJ. GUIDE

PROF.R.O. GAWANDE

PROF.R.O. GAWANDE

DEPARTMENT OF MECHANICAL ENGINEERING

SHREERAM POLYTECHNIC

AIROLI

THANE

YEAR 2010-2011

ACKNOWLEDGEMENT

We express esteemed gratitude and sincere thanks to our worthy

lecturer guide Prof PROF.---------------- , our vocabulary does not have suitable

words benefiting to high standard of knowledge and extreme sincerity deviation

and affection with which have regularly encouraged us to put heart and soul in

this work.

We are also thankful to our workshop Superintendent, and assistants,who helped

a lot, for completion of this project. Our parents and relatives who always bear

with us in very critical situation have contributed a great deal in making this

true for us. We give expression of our love and appreciation for them with our

heart in full.

Thanking,

---------DEFINATION OF PROJECT-----------

P => Planning before carrying out the work

R => Raw material required for the work

O => Organization of the work

J => Joint effort put in to the work.

E => Estimation of material required in the work.

C => Costing of thework.

T => Techniques used in performing.

INDEX

Page.No

Name of the topic Page No.

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

CAPTER NO 1

INTRODUCTION

To days world requires speed on each and every field. Hence rapidness and

quick working is the most important. Now a days for achieving rapidness,

various machines and equipments are manufactured by man. The engineer is

constantly conformed to the challenges of bringing ideas and design in to

reality. New machines and techniques are being developed continuously to

manufacture various products at cheaper rates and high quality. The project

“GEARLESS TRANSMISSION” being compact and Portable equipment, which is

skillful and is having some thing precise in transmitting power at right angle

with out any gears being manufactured. Most of the material is made available

by our college. The parts can be easily made in our college work-shop. It’s price

is also less. This project gives us knowledge, experience , skill and new ideas of

manufacturing. It is a working project and having guarantee of success. This

project is the equipment useful to improve the quality of the gear being

manufactured and can be made in less time, hence we have selected this

project.

El-bow mechanism is an ingenious link mechanism of slider and kinematic

chain principle. This is also called as “gearless transmission mechanism”

The mechanism is very useful for cornering or transmitting motions at right angles. However in certain industrial application “Gearless Transmission at Right Angle “can also work at obtuse or accurate angle plane can be compared to worm and worm gear or bevel and pinion gear which are invariably used in the industry for numerous application. The main feature for mechanism

comparatively high efficiency between the input and the output power shafts

with regards to the gear efficiencies.

It has elaborately discussed in detail in the entire books o engineering that the

gear drives have very low mechanical efficiencies. Since Factor relating to

under frictional Forces between the mating gear teeth, the erratic hunting of

the gears, the back lash between the teeth can not be over come and hence

the efficiency can not be more than 55%

Of recent gears of warm bevel type are being manufactured in poly propqlene

and epoxy material where the Frictional Forces are comparatively eliminated.

Even though such gears are used for relatively small applications the efficiency

is not more than 42%.

The El-bow Mechanism transmits the I/P power towards the O/P side such a

way that the angular Forces produced in the slacks are simply transmitted with

the help of pins which takes up the I/P power and the right angle drive is

transferred towards the O/P slack and pin assembly.

Hence very little friction plays while the power is being transmitted; the

hunting and back lash one absent. Therefore, it is appreciated that efficiency as

high as 90-92% are possible in gear less transmission mechanism.

Here we are going to show two applications of El-bow mechanism. How it will become work, which we are showing by cutting the wood by attaching the wood cutter at the output shaft as well as we are also making it as compressor. It will suct the air from atmosphere, compressor it &delivers it at high pressure. As we

were calculate the result obtained is we can get the compressed air at

pressure 2 bar.

The first application of this mechanism was made use of the “Big Ben Clock”

having four dials on the tower of London. This clock was installed some time

between 1630 to 1635 AD. And still it is functioning in good condition.

CAPTER NO 2

WORKING

Here is a wonderful mechanism that carries force through a 90º bend.

Translating rotational motion around an axis usually involves gears, which

can quickly become complicated, inflexible and clumsy-looking, often ugly.

So, instead of using gears, this technology elegantly converts rotational

motion using a set of cylindrical bars, bent to 90º, in a clever, simple and

smooth process that translates strong rotational force even in restricted spaces.

A gearless transmission is provided for transmitting rotational velocity from

an input connected to three bent links. Both the input shaft and the housing

have rotational axes. The rotational axis of the input shaft is disposed at an

angle of 90 degree with respect to the rotational axis of the housing. As a

result, rotation of the input shaft results in a processional motion of the axis of

the bent link. The rotary and reciprocating motion of bent link transmit

rotation of prime mover to 90 degree with out any gear system to an output

shaft without gears. The transmission includes an input shaft.

CAPTER NO 3

CONCEPT DRAWING OF MACHINE

ROTATING SHAFT DIA 20 MM

BASE PLATE

BENT LINK DIA 10 x 240 mmmm

MOTOR ¼ hp 1440 RPM SINGLE PHASE

PULLY 250 mm dia

P204 BEARING

PIN HOUSING 62 x 95 MM DIA

PULLY 45 mm dia TRANSMISSION A-56

CAPTER NO 4

WORKING

The Gearless transmission or El-bow mechanism is a device for transmitting

motions at any fixed angle between the driving and driven shaft.

The synthesis of this mechanism would reveal that it comprises of a number

of pins would be between 3 to 8 the more the pins the smoother the

operation.

These pins slide inside hollow cylinders thus formatting a sliding pair. Our

mechanism has 3 such sliding pairs. These cylinders are placed in a hollow

pipe and are fastened at 120* to each other. This whole assembly is

mounted on brackets wooden table. Power is supplied by an electric motor.

The working of the mechanism is understood by the diagram. An unused

form of transmission of power on shaft located at an angle.

Motion is transmitted from driving to the driven shaft through the roads

which are bent to conform to the angles between the shafts. These roads are

located at in the holes equally spaced around a circle and they are free to

slide in & out as the shaft revolves. This type of drive is especially suitable

where quite operation at high speed is essential but only recommended for

high duty.

The operation of this transmission will be apparent by the action of one rod. During a revolution. If we assume that driving shaft ‘A’ is revolving as indicated by arrow the driven shaft B will rotate counter clockwise. As shaft A

turns through half revolution C shown in the inner and most effective driving

position slides out of both shafts A & B.

The first half revolution and rod “C” then will be at the top then during the

remaining half this rod “C” slide in wards until it again reaches to inner most

position shown in Fig. in the meanwhile the other roads have of course

passed through the same cycle of movements all rods are successively sliding

inwards and outwards.

Although this transmission is an old one many mechanics are skeptical about

its operation, however it is not only practicable but has proved satisfactory

for various applications when the drive is for shafts which are permanently

located at given angle. Although this illustration shows a right angle

transmission this drive can be applied also to shafts located at intermediate

angle between 0* and 90*.

In making this transmission, it is essential to have the holes for a given rod

located accurately in the same holes must be equally spaced in radial and

circumferential directions, be parallel to each rod should be bent to at angle

at which the shaft are to be located. If the holes drilled in the ends of the

shafts have ‘blind’ or closed ends, there ought to be a small vent at the

bottom of each rod hole for the escape of air compressed by the pumping

action of the rods. These holes are useful for oiling to avoid blind holes shafts

may have enlarged port or shoulder. This transmission may be provided

centrally and in line with the axis of each shaft and provided with a circular

groove at each rod or a cross-pin to permit rotation of the shaft about the

rod simply active as a retaining device for shipping and handling purposed.

As mentioned in first chapter that we are showing two applications of this

mechanism at a time.

1) As a wood cutting machine

The cutter is attached on the output shaft when motion is transmitted

through mechanism to output shaft the shaft will start to rotate at

adjusted speed.

The speed is adjusted by means of pulley (i.e.…..RPM). The cutters will

also start to rotate along with the shaft the because of cutter is

250mm. the through slot introduces in the table for free rotation of

cutter edges in table. Now the feed given to wooden rods or plywood

to cut in desire shape and size.

The speed is adjusted by means of pulley (i.e.…..RPM). The

cutters will also start to rotate along with the shaft the because of

cutter is 250mm. the through slot is introduced in the table. Now feed

given to wooden rods or plywood to cut in desired shape and size.

2) As a air compressor or air pump -> the compressor or and pump also

introduced in our project when the pins inside the drilled holes are

reciprocates as well as revolves along the axis of cylinder it gives the

compressor effect. Among the three pins when first pin goes at inner

dead center it sucts the air then it start to move at outer dead center

by revolving, it compresses the air against seal and cylinder head disc

and does simultaneously by three pins and we can get continue

discharge of air the quantity.

3) Mechanical seal is defined as a devise which seals by virtue of axial

contact pressure between two relatively flat surfaces in a plane right

angle to the axis of the shaft.

The seal used in EL-BOW m/c compressor is stationary type. It is place

between cylinder and cylinder head.

CAPTER NO 5

APPLICATION

The featured product has its widest application as an extension for a socket

wrench. Here the design makes it easy to reach fasteners in the automotive

and other mechanical industries, where direct access to bolts and screws is

often limited. However, the possible applications for this technology extend

into numerous fields. Just think of the possibilities for power transmission in

push bikes, toys and hand-cranked equipment, or for movement transmission

in store and outdoor signage.

1. Driving for all kinds four faced tower clocks. The elbow mechanism

was first use in the year 1685 for the famous London tower clock

named bigben.

2. The mechanism is invariable used for multiple spindle drilling

operation called the gang drilling

3. Used for angular drilling between 0 to 90 degree position.

4. Lubrication pump for C.N.C. lathe machines.

5. The mechanism is very useful for a reaching a drive at a clumsy

location.

6. Air blower for electronic and computer machine.

7. The mechanism has found a very usefully use in electronic and

computer technology for multiple.

8. The elbow mechanism is used for movement of periscope in

submarines, the year 1685 for the famous London tower clock

named bigben.

CAPTER NO 6

COMPARISON

COMPARISON OF GEARED DRIVE WITH GEARLESS DRIVE

The gearless drive is capable of transmitting motion at any fixed angle

between 0* to 90*. This desired effect is also possible with help of

bevel gearless differ to a great extent not only in their manufacturing

method or working principle but also in other aspects etc. the aspects

have been discussed below:

I) MANUFACTURING METHODS

Bevel gears, which are straight teeth or spiral teeth are manufactured on

special purposes machines like “Gearless machines”. These required

large amount of calculation and every pair or set of gear are made

together and there is no interchangeability.

The gearless drive has this advantage that it can be machined and

manufactured on conventional machines an it provide complete

freedom of interchangeability.

II) WORKING PRINCIPLE:-

A gear comprises of a frustum of a cone with teeth out on its periphery.

The driving gear mounted on the input shaft meshes with the driven

gear and thus provides motion at right angle to the input shaft.

The working of the gearless drive has been explained in the earlier

chapter and it obviously very different from the above-

]

III) CAUSE OF FAILURE:-

Starting with the principle that failure id the result of the stress I.e.

condition more severe then the material can with stand. The various

type of failures such as pitting, corrosion, erosion, fatigue etc. Cause

the wearing of the gear tooth resulting in the tooth leads to the

replacement of the entire gear set, which is very expensive.

The effect of pitting, erosion, corrosion etc. will be present in the

gearless drive also but the effect of these will be not be as severe as in

the case of geared drive, failure will take place in the pi s ton

e.g. ..Either bending or crack. Of the pins, but the main advantage is

that only particular pin will have to be replaced instead of case of

failure.

VI) MATERIAL:-

The material chosen for any component must (a) be easily available (b)

be capable of being processed in the desire deaminations and (c) have

the necessary physical properties. The gears generally fail due to

bending, fatigue and impact and the gears are also responsible for the

failure of the components in the gears have to very carefully determined

since it may lead to pitting.

V) LUBRICATION AND COOLING:-

A few open gears drives are lubricated by grease but gear units are

usually totally enclosed and oil lubricated. The arrangement for

lubrication is simple and easy, since it requires only a leak proof

housing in which the gears are placed and oil is filled. This lubricating

also acts as cooling medium. The heat generated and it then spreads to

other areas.

In the gearless drive lubrication and cooling plays a

very major role. The efficiency of the mechanism is affected by

lubrication. Although the system of lubrication and cooling complex as

discussed in the next chapter but gives good result. Due to sliding

contract, between pins and cylinders, heat generated is more and thus

effective cooling is a must.

VI) TORQUE TRANSMITTUNG CAPACITY:-

The gear drive is capable of transmitting very high torque as

compared to the gearless drive which is ment only for low torque applications.

VII) LIFE AND EFFICIENCY:-

Designed life represents the total period of operation, regardless of any

variations of torque or speed, which may occur during that the time industrial

The geared drive is capable of giving an efficiency of about 40% and certain

errors like backlash, hunting etc… can not be eliminated.

In the gearless drive, although the life has not been calculated but it is

assumed that its life will be in comparison to that of geared drive but its

efficiency could be as high as 85% to92% with proper lubrication and cooling.

VIII) Comparison of this drive with gear drive infinite no of speed can be

available which can not to easily possible in gearbox.

IX) Optimum machining is important which require exact machining speed

for particular operation which is very difficult to gain for gear drive but can

easily available by this drives increase the following.

1) Tool life

2) Productively

3) Energy saving.

X) The different speed at eight angle (0 to 90) is possible which is not easily

possible in gear drive

XI) Efficiency can be increased by increasing no of pins, by precise

machining, selecting suitable material and proper lubrication.

CAPTER NO 7

SELECTION OF MATERIAL

The proper selection of material for the different part of a machine is

the main objective in the fabrication of machine. For a design engineer it is

must that he be familiar with the effect, which the manufacturing process and

heat treatment have on the properties of materials. The Choice of material for

engineering purposes depends upon the following factors:

1. Availability of the materials.

2. Suitability of materials for the working condition in service.

3. The cost of materials.

4. Physical and chemical properties of material.

5. Mechanical properties of material.

The mechanical properties of the metals are those, which are associated with

the ability of the material to resist mechanical forces and load. We shall now

discuss these properties as follows:

1. Strength : It is the ability of a material to resist the externally applied

forces

2. Stress: Without breaking or yielding. The internal resistance offered by

a part to an externally applied force is called stress.

3. Stiffness: It is the ability of material to resist deformation under

stresses. The modules of elasticity of the measure of stiffness.

4. Elasticity: It is the property of a material to regain its original shape

after deformation when the external forces are removed. This property

is desirable for material used in tools and machines. It may be noted

that steel is more elastic than rubber.

5. Plasticity: It is the property of a material, which retain the deformation

produced under load permanently. This property of material is

necessary for forging, in stamping images on coins and in ornamental

work.

6. Ductility: It is the property of a material enabling it to be drawn into

wire with the application of a tensile force. A ductile material must be

both strong and plastic. The ductility is usually measured by the terms,

percentage elongation and percent reduction in area. The ductile

materials commonly used in engineering practice are mild steel, copper,

aluminum, nickel, zinc, tin and lead.

7. Brittleness: It is the property of material opposite to ductile. It is the

property of breaking of a material with little permanent distortion.

Brittle materials when subjected to tensile loads snap off without giving

any sensible elongation. Cast iron is a brittle material.

8. Malleability: It is a special case of ductility, which permits material to

be rolled or hammered into thin sheets, a malleable material should be

plastic but it is not essential to be so strong. The malleable materials

commonly used in engineering practice are lead, soft steel, wrought

iron, copper and aluminum.

Toughness: It is the property of a material to resist the fracture due to high impact loads like hammer blows. The toughness of the material decreases when it is heated. It is measured by the amount of absorbed after being

9. stressed up to the point of fracture. This property is desirable in parts

subjected to shock an impact loads.

10.Resilience: It is the property of a material to absorb energy and to resist

rock and impact loads. It is measured by amount of energy absorbed per

unit volume within elastic limit. This property is essential for spring

material.

11.Creep: When a part is subjected to a constant stress at high temperature

for long period of time, it will undergo a slow and permanent

deformation called creep. This property is considered in designing

internal combustion engines, boilers and turbines.

12.Hardness: It is a very important property of the metals and has a wide

verity of meanings. It embraces many different properties such as

resistance to wear scratching, deformation and mach inability etc. It also

means the ability of the metal to cut another metal. The hardness is usually

expressed in numbers, which are dependent on the method of making the

test. The hardness of a metal may be determined by the following test.

a) Brinell hardness test

b) Rockwell hardness test

c) Vickers hardness (also called diamond pyramid) test and

d) Share scaleroscope.

The science of the metal is a specialized and although it overflows in to realms of knowledge it tends to shut away from the general reader. The knowledge of materials and their properties is of great significance for a design engineer. The machine elements should be made of such a material which has properties suitable for the conditions of operations. In addition to this a design engineer must be familiar with the manufacturing processes and the heat treatments have on the properties of the materials. In designing the various part of the machine it is

necessary to know how the material will function in service. For this certain

characteristics or mechanical properties mostly used in mechanical

engineering practice are commonly determined from standard tensile tests. In

engineering practice, the machine parts are subjected to various forces, which

may be due to either one or more of the following.

1. Energy transmitted

2. Weight of machine

3. Frictional resistance

4. Inertia of reciprocating parts

5. Change of temperature

6. Lack of balance of moving parts

The selection of the materials depends upon the various types of stresses that

are set up during operation. The material selected should with stand it.

Another criteria for selection of metal depend upon the type of load because a

machine part resist load more easily than a live load and live load more easily

than a shock load.

Selection of the material depends upon factor of safety, which in turn depends

upon the following factors.

1. Reliabilities of properties

2. Reliability of applied load

3. The certainty as to exact mode of failure

4. The extent of simplifying assumptions

5. The extent of localized

6. The extent of initial stresses set up during manufacturing

7. The extent loss of life if failure occurs

8. The extent of loss of property if failure occurs

Materials selected in m/c

Base plate, motor support, sleeve and shaft

Material used

Mild steel

Reasons:

1. Mild steel is readily available in market

2. It is economical to use

3. It is available in standard sizes

4. It has good mechanical properties i.e. it is easily machinable

5. It has moderate factor of safety, because factor of safety results in

unnecessary wastage of material and heavy selection. Low factor of

safety results in unnecessary risk of failure

6. It has high tensile strength

7. Low co-efficient of thermal expansion

Properties of Mild Steel:

M.S. has a carbon content from 0.15% to 0.30%. They are easily wieldable

thus can be hardened only. They are similar to wrought iron in properties.

Both ultimate tensile and compressive strength of these steel increases with

increasing carbon content. They can be easily gas welded or electric or arc

welded. With increase in the carbon percentage weld ability decreases.

Mild steel serve the purpose and was hence was selected because of the above

purpose

BRIGHT MATERIAL:

It is a machine dawned. The main basic difference between mild steel and

bright metal is that mild steel plates and bars are forged in the forging

machine by means is not forged. But the materials are drawn from the dies in

the plastic state. Therefore the material has good surface finish than mild steel

and has no carbon deposits on its surface for extrusion and formation of

engineering materials thus giving them a good surface finish and though

retaining their metallic properties

RAW MATERIAL & STANDARD MATERIAL

SR NO PART NAME MAT QTY DECREPTION

1 FRAME ms1 C SECTION 75 X 40 X 4

MM

2 MOTOR STD 1 0.25 HP 1440 RPM

3 SHAFT ms 2 DIA 20 MM X 350 MM

4 HOUSING ms 2 DIA 95MM X 62 MM

5 BENT LINK MS 3 DIA 10 MM X 240 MM

6 PULLEY CI 2 DIA 45 & DIA 250 MM

7PEDESTAL BEAREING

CI4

P204

8 BELT leather 1 A - 56

9 ANGEL MS 1 35 X 35 X 5 MM

10 NUT BOLT WASHER Ms 10 M 10

11 WELDING ROD -

12 COLOUR -

CAPTER NO 6

MACHIN DESIGN

The subject of MACHINE DESIGN deals with the art of designing

machine of structure. A machine is a combination of resistance bodies with

successfully constrained relative motions which is used for transforming

other forms of energy into mechanical energy or transmitting and modifying

available design is to create new and better machines or structures and

improving the existing ones such that it will convert and control motions

either with or without transmitting power. It is the practical application of

machinery to the design and construction of machine and structure. In order

to design simple component satisfactorily, a sound knowledge of applied

science is essential. In addition, strength and properties of materials

including some metrological are of prime importance. Knowledge of theory

of machine and other branch of applied mechanics is also required in order

to know the velocity. Acceleration and inertia force of the various links in

motion, mechanics of machinery involve the design.

CONCEPT IN M.D.P.

Consideration in Machine Design When a machine is to be designed

the following points to be considered: -

i) Types of load and stresses caused by the load.

ii) Motion of the parts and kinematics of machine. This deals with the

iii) type of motion i.e. reciprocating . Rotary and oscillatory.

iv) Selection of material & factors like strength, durability, weight,

corrosion resistant, weld ability, machine ability are considered.

v) Form and size of the components.

vi) Frictional resistances and ease of lubrication.

vii) Convience and economical in operation.

viii)Use of standard parts.

ix) Facilities available for manufacturing.

x) Cost of making the machine.

xi) Number of machine or product are manufactured.

GENERAL PROCEDURE IN MACHINE DESIGN

The general steps to be followed in designing the machine are as

followed.

i) Preparation of a statement of the problem indicating the

ii) purpose of the machine.

iii) Selection of groups of mechanism for the desire motion.

iv) Calculation of the force and energy on each machine member.

v) Selection of material.

vi) Determining the size of component drawing and sending for

manufacture.

vii) Preparation of component drawing and sending for

manufacture.

viii)Manufacturing and assembling the machine.

` Testing of the machine and for functioning

Power of motor = ¼ H.P = 746 x .25 = 186.5 N- m /s

Rpm of motor = 1440 rpm

Power of motor = P = 186.5 watt.

2π N T

P = -----------------

60

Where, N = Rpm of motor = 1440

T = Torque transmitted

2π x 1440 x T

186.5 = ----------------------

60

T = 1.23 N-m

T = 1238 N-mm

DESIGNING OF SHAFT

BENDING:

The material forces that are developed on any cross section of the shaft give

rise to stresses at every point. The internal or resisting moment gives rise to

so called bending stresses.

TORSION:

When the shaft is twisted by the couple such that the axis of the shaft and

the axis of the couple coincides, the shaft is subjected to pure torsion and

the stresses at any point of cross section is torsion or shear stresses.

COMBINED BENDING AND TORSION:

In practice the shaft in general are subjected to combination of the above

two types of stresses. The bending stresses may be due to following

1. Weight of belt

2. Pull of belts

3. Eccentric Mounting

4. Misalignment

The torsional movement on the other hand may be due to direct or indirect

twisting. Thus any cross-section of the shaft is subjected simultaneously of

both bending stresses and torsional stresses.

Following stresses are normally adopted in shaft design

Maxm tensile stress = 60 N/mm2

Maxm shear stress = 40 N/mm2

Shaft design on basic of study

Considering 25 % overload

Tmax = 1238 x 1.25

= 1.525 x 103 N-mm

The shaft is subject to pure torsional stress

We know

T= 3.14/16 x fs x d3

15250 = 3.14/16 x 70 x d3

D = 10.20 mm

Taking factor of safety = 2

D = 10 x 2 = 20 mm

Same torque is transmitted to bent link shaft

So torque on each shaft = T /3 = 15250 /3 = 5083 N mm

T= 3.14/16 x fs x d3

5083 = 3.14/16 x 70 x d3

D = 7.17 mm

Taking factor of safety = 1.4

D = 7 x 1.4 = 9.8 = 10 mm

DESIGN OF C-SECTION

Material: - M.S.

The vertical column channel is subjected to bending stress

Stress given by => M/I = fb / y

In above equation first we will find the moment of inertia about x and y

Axis and take the minimum moment of inertia considering the channel of

ISLC 75 x 40 size.

l = 40

B = 75 t = 5

b = 65

We know the channel is subject to axial compressive load

In column section the maximum bending moment occurs at channel of section

M = Ra x L/2

M = 750 x 1500/2

M = 562500 N-mm

We know

fb = M/Z

Z = t (l x b + (b2/6))

Z = 5 (40 x 65 + (652/6))

Z = 3304 mm3

Now check bending stress induced in C section

fb induced = M/Z

fb induced = 562500 /3304 = 170.25 N / mm2

As induced stress value is less than allowable stress value design is safe.

fb = Permissble bending stress = 320 N / mm²

fb induced < fb allowable

Hence our design is safe.

DESIGN OF WELDED JOINT OF CHANNEL :

The welded joint is subjected to pure bending moment . so it should be design for bending

stress. We know minimum area of weld or throat area

A = 0.707 x s x l

Where s = size of weld

l = length of weld

A = 0.707 x 5 x ( 75 + 40 + 35 + 58 +35 )

A = 0.707 x 5 x 243

A = 859 mm2

Bending strength of parallel fillet weld

P = A x fb fb = 80 N / mm2

As load applied at the end of lever is 250 N . So moment generated at the welded joint is

M =P x L

= 250x 450

= 112500 N – mm

we know fb = M /Z

BH3 – bh3

Z = --------------------------------

6H

40 x 753 – 35 x 583

Z = ----------------------------------

6 x 75

Z = 209824

Calculating induce stress developed in welded joint

fb induced = 112500 / 209824

= 0.536 N /mm 2

As induce stress is less then allowable stress the design is safe.

DESIGN FOR WELDED JOINTS:-

Diameter of shaft = D = 20 mm.

Size of weld = s = 4 mm

loadfs = -----------------

shear area

600 = ----------------- π .D x t

600 = ----------------- π x 20 x t

now, t = s.cos45 = 0.707 s

9.55

.fs = ---------------- N/mm2

0.707 x 4

fs = 3.37 N/mm2

As induced stress value is less than allowable value, which is 56 N/mm2

So design is safe.

CHAPTER NO

COST ESTIMATION

Cost estimation may be defined as the process of forecasting the

expenses that must be incurred to manufacture a product. These expenses

take into a consideration all expenditure involved in a design and

manufacturing with all related services facilities such as pattern making,

tool, making as well as a portion of the general administrative and selling

costs.

PURPOSE OF COST ESTIMATING:

1. To determine the selling price of a product for a quotation or contract

so as to ensure a reasonable profit to the company.

2. Check the quotation supplied by vendors.

3. Determine the most economical process or material to manufacture

the product.

4. To determine standards of production performance that may be used

to control the cost.

BASICALLY THE BUDGET ESTIMATION IS OF TWO TYRES:

1. material cost

2. Machining cost

MATERIAL COST ESTIMATION:

Material cost estimation gives the total amount required to collect the raw

material which has to be processed or fabricated to desired size and

functioning of the components.

These materials are divided into two categories.

1. Material for fabrication:

In this the material in obtained in raw condition and is manufactured or

processed to finished size for proper functioning of the component.

1. Standard purchased parts:

This includes the parts which was readily available in the market like allen

screws etc. A list is forecast by the estimation stating the quality, size and

standard parts, the weigh of raw material and cost per kg. For the fabricated

parts.

MACHINING COST ESTIMATION:

This cost estimation is an attempt to forecast the total expenses that may

include to manufacture apart from material cost. Cost estimation of

manufactured parts can be considered as judgment on and after careful

consideration which includes labour, material and factory services required

to produce the required part.

PROCEDURE FOR CALCULATION OF MATERIAL COST:

The general procedure for calculation of material cost estimation is

1. After designing a project a bill of material is prepared which is divided

into two categories.

a. Fabricated components

b. Standard purchased components

2. The rates of all standard items are taken and added up.

3. Cost of raw material purchased taken and added up.

LABOUR COST:

It is the cost of remuneration (wages, salaries, commission, bonus etc.) of

the employees of a concern or enterprise.

Labour cost is classifies as:

1 Direct labour cost

2 Indirect labour cost

Direct labour cost:

The direct labour cost is the cost of labour that can be identified directly

with the manufacture of the product and allocated to cost centers or cost

units. The direct labour is one who counters the direct material into saleable

product; the wages etc. of such employees constitute direct labour cost.

Direct labour cost may be apportioned to the unit cost of job or either on the

basis of time spend by a worker on the job or as a price for some physical

measurement of product.

Indirect labour cost:

It is that labour cost which can not be allocated but which can be apportioned to or absorbed by cost centers or cost units. This is the cost of labour that doesn’t alters the construction, confirmation, composition or condition of direct material

but is necessary for the progressive movement and handling of product to

the point of dispatch e.g. maintenance, men, helpers, machine setters,

supervisors and foremen etc.

The total labour cost is calculated on the basis of wages paid to the labour

for 8 hours per day.

Cost estimation is done as under

Cost of project = (A) material cost + (B) Machining cost + (C) lab our

cost

(A) Material cost is calculated as under :-

i) Raw material cost

ii) Finished product cost

i) Raw material cost:-

It includes the material in the form of the Material supplied by the “Steel

authority of India limited” and ‘Indian aluminum co.,’ as the round bars,

angles, square rods, plates along with the strip material form. We have to

search for the suitable available material as per the requirement of designed

safe values. We have searched the material as follows:-

Hence the cost of the raw material is as follows:-

RAW MATERIAL & STANDARD MATERIAL

SR NO

PART NAME MAT QTY COST

1 FRAME ms 1 1500

2 MOTOR STD 1 1800

3 SHAFT ms 2 500

4 HOUSING ms 2 800

5 BENT LINK MS 3 350

6 PULLEY CI 2 600

7 PEDESTAL BEAREING CI 4 1200

8 BELT leather 1 150

9 ANGEL MS 1 200

10 NUT BOLT WASHER Ms 10 100

11 WELDING ROD - 220

12 COLOUR - 100

TOTAL 7520 /-

Total cost (miscellaneous)

1. Machining cost 2500/-

2. Design 200/-

3. Drawing 380/-

4. Transportation & communication 200/-

There for,

1) Total cost of parts = 75200.00

2) Miscellaneous = 2500.00

= 200.00

= 380.00

= 200.00

Grand total cost in Rs. = 10800.00

CHAPTER: 7

SPECIFICATION & MANUFACTURING OF PRRTS

MANUFACTURING PROCESS :

The following are the various manufacturing process used in

mechanical engineering.

1) Primary Shaping Process :

The process used for the preliminary shaping of the machine

component is known as primary shaping process.

2) Machine Process :

The process used for giving final shape to the machine component,

according to planned dimensions is known as machining process. The

common operation drilling, boring etc.

3) Surface Finishing Process :

The process used to provide a good shape surface finish for the machine

components are known as surface finishing processes. The common operation

used for the process are polishing, buffing, lapping etc.

4) Joining Process :

The process used for joining machine components are known as joining

process. The common operation used for this process are soldering, brazing,

welding etc.

5) Process Affecting Change In Properties :

These are intended to import specific properties to material e.g. heat

treatment, hot working, cold rolling etc.

WELDED JOINTS :

Definition :

A welded joint is a permanent joint, which is obtained by the fusion of

the edges of the two parts, to be joined together, with or without the

application of pressure and a filler material.

Welding is intensively used in fabrication as an alternative method for

casting or forging and as a replacement for bolted and reverted joints. It is also

used as a repair medium.

Advantages :

1) The welded structures are usually lighter than riveted structures.

2) The welded joints provide maximum efficiency which to impossible

innervated joints.

3) Alteration and addition can be easily made.

4) As the welded structure is smooth in appearance, it is good looking.

5) In welded structures, tension members are not weakened.

6) In a welded joint has high strength often more than parent metal.

Disadvantages :

1) Since there is uneven heating and cooling during fabrication therefore the

members may get distorted as additional stresses may develop.

2) It requires a highly skilled labour and supervision.

3) No provision for expansion and contraction in the frame, therefore there is

possibility of cracks.

4) The inspection of welding work is difficult than riveting work.

V - BELT AND ROPE DRIVERS :

V - belt is mostly used in factories and workshops where a great

amount of power is to be transmitted from one pulley to another then the two

pulleys are very near to each other.

The V - belt are made of fabric and cords moulded in rubber and

covered in fabric and rubber. The power is transmitted by the wedging action

between the belt and the v - groove in the pulley as sheave.

Advantages :

1) The drive is positive.

2) Since the v - belts are made endless and there is no joint cable, therefore

the drive is smooth.

3) It provides larger life, 3 to 5 years.

4) It can be easily installed and removed.

5) The operation of the belt and pulley is quiet.

6) The belt have the ability to cushion the shack when the machines are

started.

7) The wedging action gives high value of limiting friction therefore power

transmitted by v - belts is more than flat belts for the same coefficient of

friction, are of contact and allowable tension.

Disadvantages :

1) The v - belt drive connect be used with large centre distances because of

larger weight, for unit length.

2) The v - belt are not so durable as flat.

3) The construction of pulleys for v - belts is more complicated than pulleys

of flat belt.

4) Since the v - belts are subjected to certain amount of creep, therefore not

suitable for constant speed applications.

5) The belt life is greatly influenced with temperature changes, improper belt

tension and mismatching of belt lengths.

COMPONENT: FRAME CHANNEL

MATERIAL:- M.S. CHANNEL

MATERIAL SPECIFICATION:-I.S.L.C. 40X.75X5

SR. NO

DESCRIPTION OF OPERATION

MACHINE USED

CUTTING MEASUREMENT TIME

1 Cutting the channel in to length of 1000 mm long

Gas cutting machine

Gas cutterSteel rule

15min.

2 Cutting the channel in to length of 480 mm long

Gas cutting machine

Gas cutter Steel rule 15min.

3 Filing operation can be performed on cutting side and bring it in perpendicular C.S.

Bench vice File Try square 15 min.

4 Weld the channels to the required size as per the drawing

Electric arc welding machine

------- Try square 20 min

5 Drilling the frame at required points as per the drawing.

Radial drill machine

Twist drill Vernier calliper 10 min.

NAME OF THE PART – PIN

MATERIAL – BRIGHT STEEL

QUANTITY – 3

SR.NO. DETAIL OPER. M/C. USED TOOL USED ACCES MEA.INST.

1. Marking on shaft - - - Scale

2. Cutting as per dwg

Power hack saw

Hock saw blade

Jig & fixtures

Scale

3. Facing both side of shaft

Lathe machine

Single point cutting tool

Chuck Vernier caliper

4. Turning as per dwg size

- - - -

5. bending Gas cutting

Right angle vice -

6. Filling on both end

Flat file Vice -

NAME OF THE PART –HOUSING

MATERIAL –BRIGHT STEEL

QUANTITY –2

SR.NO. DETAIL OPER. M/C. USED TOOL USED ACCES MEA.INST.

1. Marking on shaft

- - - Scale

2. Cutting as per dwg

Power hack saw

Hock saw blade

Jig & fixtures

Scale

3. Facing both side of shaft

Lathe machine

Single point cutting tool

Chuck Vernier caliper

4. Turning as per dwg size

- - - -

5. Drilling 3 hole

drilling m/c.

drill - Vernier caliper

6. Filling on both end

Flat file Vice -

COMPONENT: PULLEY

MATERIAL:- C.I

QUANTITY : - 2

SR. NO

DESCRIPTION OF OPERATION

MACHINE USED

CUTTING MEASUREMENT TIME

1 Take standard pulley as per design

------ ---------- ------------- ---------

2 Face both side of hub portion

Lathe machine

Single point cutting tool

Vernier caliper 15 min.

3 Hold it in three jaw chuck & bore inner dia as per shaft size

Lathe machine

Single point cutting tool

Vernier caliper 20 min.

4 Drilling the hub at required points as per the drawing

Radial drill machine

Twist drill Vernier calliper 10 min.

5 Tap the hub at drill area.

Hand tap set

Tap Vernier calliper 10 min.

CHAPTER: 8POSSIBLE IMPROVEMENTS

ANDADVANCES

The project designed and manufactured by us although is only model and has

not undergone any extensive research or study but we are quite confident that

it is possible to improve it’s efficiency to a considerable extent by improving

the manufacturing techniques and also by corporative certain modifications.

This device can also be used for various other applications besides just

transmitting motion at desired angle those applications have discussed in

detailing the following: -

METHOD OF IMPROVING EFFICIENCY: -

Manufacturing of improving efficiency: -

The main motion is transmitted with the help of a sliding pair which formed

between pin & the cylinder. These pins have to be lapped and cleaned and it

should be capable of providing complete interchangeability similarly with the

cylinder, they too have to be hone or lapped so a to provide smooth surface

finish. This will result in less frictional loss and loss heat generation.

Lubrication and cooling methods: -

Lubrication and cooling are a must in sliding members. One of the simple

techniques applied for lubrication can be to drill oil holes in the cylinder body

for fill than up with oil. But this technique will not be very effective since the

weight and use of cylinders will increase.

Modifications: -

One of the methods by which efficiency or performance can be enhanced is by

increasing the number of pins. From the working of the mechanism we know

that the pin at the inner most position is the drawing pin the pins the

mechanism. Thus if the no. required for the next pin to attain the inner most

position is considerable reduced and thus the performance of the mechanism

& its life increases.

POSSIBLE ADVANCE

We can also use this transmission system as

1. As lubricating pump while transmitting power.

2. Steam engine (eliminating the crank of shaft & complicated

valve system).

LUBRICATING PUMP

The small change which have to incorporate for this purpose is to place

stationary disc at the rear and it so fits with the cylinder that it avoids leak

ages.

WORKING

The slot position and length is so that adjusted that when pin is at inner most position cylinder meshes with the suction port & suction of oil is started the slot remains open till pin given maximum outward stroke, after that cylinder end is closed by the dics. Now the pin starts moving inwards and thus compression stroke commences. The delivery slot location is so adjusted that after the completion of 80 to 85% of compression stroke, the cylinder meshes with the delivery stroke & thus the compressed fluid is discharged at high pressure. The delivery slot length was such adjusted that remains in mesh with cylinder for 15 to 20% of

compression for complete delivery of the compressed fluid. The suction slot

length is adjusted for complete outward stroke of pin.

Advantages

Due to such an inbuilt pump we do not require any external pump

As soon as mechanism is started lubrication system automatically starts.

The pump is of the displacement type.

Necessity for lubrication of the mechanism is eliminated.

As a steam engine

Modification for the steam engine is same as that for the pump. The only

difference is in position & the size.

WORKING: -

Here, the inlet slot position the cylinder just meshes with the inlet slot & high

pressure steam is admitted in the cylinder & thus does work on pin & pushes

the pin toward s the outer most position..

When the pin is at the outer most position, the cylinder meshes with the

delivery slot & thus delivery stroke starts & steam is driven out. After the pin

is reached the innermost position again suction stroke starts.

ADVANTAGES: -

1) Mechanism is very simply due to elimination of value

mechanisms.

2) Mechanism is small & compact.

3) No crank & crank shaft are necessary.

4) Lesser vibration because the reciprocating force are

perfectly balanced.

5) Smooth & high speed operation can be easily obtained

by cause of elimination of the value setting linkage.

DISADVANTAGES: -

1) It is only useful for small power generation.

2) It requires at least six cylinder piston pair.

3) Priming is always necessary for starting the

engine.

CHAPTER: 9

CONCLUSION

Some successful mechanical devices function smoothly however poor fly they are made while other does this only by virtue of a accurate construction & fitting of their moving parts.

This projects which looks very simple & easy to construct was actually very

difficult to conceive & imagine without seeing an actual one in practice. It is an

event a fact in the creative mental process nit the forces, which predominate

among the schemes of the active tinkers. Motions demands to be studied first &

we have done that very thing.

We find that while acceptable analysis for existing mechanism can often be made

quite easily we cannot without insight & imagination make effective synthesis of

new mechanism hence we are mould to present this our project gear less

transmission at 90* (El-bow mechanism) which we have managed to successfully

device after long & hard input in conceiving its working principle.

CHAPTER: 9

BIBLIOGRAPHY

We referred the following books,

BOOK NAME AUTHOR

Thermal Engineering R.S.Khurmi

Machine Design R.S.Khurmi

Work Shop Technology S.K.Hajra, Chaudhary